Rotary mowers which rotate about a vertical axis have been utilized by agricultural purposes for several decades. Single blades driven by power take off units from a tractor gave way to multiple blades being driven in either a synchronized manner or by locating multiple blades in an offset pattern so that the mowing patterns would overlap. As mowers have improved, cutter bar disks were added with multiple knife blades attached to each cutter bar disk. Each rotary cutter bar disk has a shape that is not necessarily completely a disk but is rather a balanced holder that may resemble a modified ellipse. The rotatory cutter bar disk includes elements to hold the knife blades therein.
Changing knives on a rotary motor or conditioner cutter bar occurs frequently. It is known to use a spring plate located as a part of the cutter bar disk to secure the knife. In order to change the knife blade, a prying mechanism is utilized to pry the spring plate so that the knife can be released and replaced. Another holding device includes the use of a clip, which is slid out using a prying mechanism. Once the blade is replaced, the clip is tapped back into place. These processes can be cumbersome and time consuming.
What is needed in the art is a knife holding system that allows for rapid changing of rotary mower/conditioner knives, particularly one that would allow changing of each knife in less than 10 seconds.